如何从 python tkinter 条目中获取整数值？

Question

so I know how entry in python works and i coded it in some projects. but in one project, there was need to get numeric ( number ) value from user in entry. but it gives the error that entry only supports string data. can you solve this problem? thanks.

Answer 1

You just need to typecast it into an integer. Eg. This code worked for me:

from tkinter import *

win=Tk()

win.geometry("700x350")

def cal_sum():
   t1=int(a.get()) # Casting to integer
   t2=int(b.get()) # Casting to integer
   sum=t1+t2
   label.config(text=sum)

Label(win, text="Enter First Number", font=('Calibri 10')).pack()
a=Entry(win, width=35)
a.pack()
Label(win, text="Enter Second Number", font=('Calibri 10')).pack()
b=Entry(win, width=35)
b.pack()

label=Label(win, text="Total Sum : ", font=('Calibri 15'))
label.pack(pady=20)
Button(win, text="Calculate Sum", command=cal_sum).pack()

win.mainloop()

Answer 2

To add further to this, you can use validation to ensure that you can only write values that evaluate to an integer in your entry:

import tkinter as tk

root = tk.Tk()
root.geometry("200x100")

# Function to validate the Entry text
def validate(entry_value_if_allowed, action):
    if int(action) == 0: # User tried to delete a character/s, allow
        return True
    try:
        int(entry_value_if_allowed) # Entry input will be an integer, allow
        return True
    except ValueError: # Entry input won't be an integer, don't allow
        return False

# Registering the validation function, passing the correct callback substitution codes
foo = (root.register(validate), '%P', '%d')
my_entry = tk.Entry(root, width=20, validate="key", validatecommand=foo)

# Misc
text = tk.Label(root, text="This Entry ^ will only allow integers")
my_entry.pack()
text.pack()
root.mainloop()

Some more info on Entry validation can be found here .